Try making the unswizzle more reliable

Author: IMS212

common/src/main/java/net/irisshaders/iris/gl/IrisRenderSystem.java

@@ -6,6 +6,7 @@
 import com.mojang.blaze3d.vertex.VertexSorting;
 import net.irisshaders.iris.Iris;
 import net.irisshaders.iris.gl.sampler.SamplerLimits;
+import net.irisshaders.iris.gl.texture.TextureType;
 import net.irisshaders.iris.mixin.GlStateManagerAccessor;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.screens.Screen;
@@ -14,6 +15,7 @@
 import org.joml.Vector3i;
 import org.lwjgl.opengl.ARBDirectStateAccess;
 import org.lwjgl.opengl.ARBDrawBuffersBlend;
+import org.lwjgl.opengl.ARBTextureSwizzle;
 import org.lwjgl.opengl.EXTShaderImageLoadStore;
 import org.lwjgl.opengl.GL;
 import org.lwjgl.opengl.GL30C;
@@ -44,6 +46,7 @@ public class IrisRenderSystem {
 	private static int polygonMode = GL43C.GL_FILL;
 	private static int backupPolygonMode = GL43C.GL_FILL;
 	private static int[] samplers;
+	private static int textureToUnswizzle;
 
 	public static void initRenderer() {
 		if (GL.getCapabilities().OpenGL45) {
@@ -486,6 +489,18 @@ public static void restoreCullingState() {
 		cullingState = true;
   }
 
+	public static void onProgramUse() {
+		if (textureToUnswizzle != 0) {
+			IrisRenderSystem.texParameteriv(textureToUnswizzle, TextureType.TEXTURE_2D.getGlType(), ARBTextureSwizzle.GL_TEXTURE_SWIZZLE_RGBA,
+				new int[]{GL30C.GL_RED, GL30C.GL_GREEN, GL30C.GL_BLUE, GL30C.GL_ALPHA});
+			textureToUnswizzle = 0;
+		}
+	}
+
+	public static void setUnswizzle(int shaderTexture) {
+		textureToUnswizzle = shaderTexture;
+	}
+
 	public interface DSAAccess {
 		void generateMipmaps(int texture, int target);
 

common/src/main/java/net/irisshaders/iris/mixin/MixinGlStateManager_FramebufferBinding.java

@@ -2,6 +2,7 @@
 
 import com.mojang.blaze3d.platform.GlConst;
 import com.mojang.blaze3d.platform.GlStateManager;
+import net.irisshaders.iris.gl.IrisRenderSystem;
 import org.lwjgl.opengl.GL30C;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Unique;
@@ -54,6 +55,8 @@ public class MixinGlStateManager_FramebufferBinding {
 			ci.cancel();
 		}
 
+		IrisRenderSystem.onProgramUse();
+
 		iris$program = pInt0;
 	}
 

common/src/main/java/net/irisshaders/iris/pipeline/programs/ExtendedShader.java

@@ -146,12 +146,6 @@ public void clear() {
 			BlendModeOverride.restore();
 		}
 
-		if (intensitySwizzle && textureToUnswizzle != 0) {
-			IrisRenderSystem.texParameteriv(textureToUnswizzle, TextureType.TEXTURE_2D.getGlType(), ARBTextureSwizzle.GL_TEXTURE_SWIZZLE_RGBA,
-				new int[]{GL30C.GL_RED, GL30C.GL_GREEN, GL30C.GL_BLUE, GL30C.GL_ALPHA});
-			textureToUnswizzle = 0;
-		}
-
 		Minecraft.getInstance().getMainRenderTarget().bindWrite(false);
 
 		super.clear();
@@ -184,7 +178,7 @@ public void apply() {
 		GlStateManager._activeTexture(i);
 
 		if (intensitySwizzle) {
-			this.textureToUnswizzle = RenderSystem.getShaderTexture(0);
+			IrisRenderSystem.setUnswizzle(RenderSystem.getShaderTexture(0));
 			IrisRenderSystem.texParameteriv(RenderSystem.getShaderTexture(0), TextureType.TEXTURE_2D.getGlType(), ARBTextureSwizzle.GL_TEXTURE_SWIZZLE_RGBA,
 				new int[]{GL30C.GL_RED, GL30C.GL_RED, GL30C.GL_RED, GL30C.GL_RED});
 		}